A jagged crystal blooms outward from a single seed.
This is the whole thing. Phluxel runs it on every cell, every step — the animation is what happens when you repeat it.
R == 0 & +(-1:1,-1:1).R > 0 & RN < 30 ? [,255,RN,RN] : [,R * 0.999,G,B]
Paste it into the Rule Editor, or pick Crystal Growth from the template list and skip the typing.
Phluxel runs in the browser as a demo, and the free desktop edition has every feature with a watermark on exports.
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